1. Field of the Invention
The present invention relates generally to apparatus for use by an electrician in stringing electrical wiring, and more particularly to an apparatus for facilitating the pulling of long lengths of wire through previously installed conduit.
2. Description of the Prior Art
Heretofore, pulling wire through a conduit has been one of the most difficult and time-consuming tasks of electricians. In accordance with present standard practices, a "fishing" line, fabricated from either steel or nylon, is fed through a conduit system to an outlet box. Subsequently, an insulated wire is connected to the trailing end of the fishing line. The leading end of the fishing line is then pulled by hand from the outlet box, thus drawing the wire through the conduit, until the wire is pulled into the outlet box. Since most outlet boxes are disposed on a wall between 12 and 18 inches above the floor, a person is required to kneel beside the outlet box and pull the line or wire with a downward thrust. Because of the proximity of the outlet box to the floor, only about six to eight inches of the wire are able to be drawn through the conduit with each pulling thrust. In almost all cases, a second person is required to push the wire from the other end of the conduit system to overcome the frictional force between the wire and the conduit. Hence, it should be realized that because of the time required to pull the line through the outlet box and the associated labor cost, the present practice results in relatively large costs to the consumer.
In the patent art, several patents teach wire pulling apparatus. In particular, U.S. Pat. No. 2,746,715 entitled "Wire Guiding Device" by V. J. Sherrod, and U.S. Pat. No. 3,113,759 entitled "Wire Puller" by H. C. Lindemark, teach wire pulling devices which include a frame having a small pulley or spool mounted therewithin and means for mounting the device to a junction box. Each of the devices serves to bend the wire as the wire is drawn over the pulley. Because of the small size of the pulleys, the wire tends to become case hardened after being drawn over the pulley. U.S. Pat. No. 3,514,048, entitled "Cable Feed Apparatus" by N. J. Lowery, teaches a cable feed apparatus which permits a cable to be wound onto, or unwound from a drum while the cable is being appropriately guided by a tubular member. The tubular member is mounted around the rim of a wheel which is rigidly fastened to a frame to prevent the wheel from rotating.